1. Technical Field
The present invention relates to an apparatus for curing thin films on substrates in general, and, in particular, to an apparatus for providing transient thermal profile processing for thin films on a moving substrate.
2. Description of Related Art
Thermal processing of thin films is often limited by the properties of substrates. Since the cost of substrates can be a significant portion of the total cost of the final product, inexpensive substrates are generally preferred. Inexpensive substrates, such as polymer or cellulose, tend to have a lower maximum working temperature than the more expensive substrates such as glass or ceramic. Thus, when thermally processing a thin film on a low-temperature substrate, the entire substrate stack is typically heated to the maximum working temperature of the substrate to minimize processing time.
Some thin film materials require a higher level of thermal processing that is not compatible with low-temperature substrates. Solutions can come in the form of increased processing time or increased temperature. The former solution increases the cost by reducing throughput and still may be inadequate for many types of thin films. The latter solution generally requires the usage of more expensive substrates that are capable of withstanding higher processing temperatures. Thus, both solutions are undesirable from an economic standpoint.